Death-penalty opponents have long complained that minorities are more likely to be executed than whites convicted of the same crime. Now a new study points up another troubling racial difference between who lives and who dies: the color of the victim.

While blacks and whites are murdered in roughly equal numbers in the USA, the killers of white people are six times as likely to be put to death, according to a statistical analysis released last week by the anti-death penalty human rights organization Amnesty International USA. It found that of 845 people executed since the U.S. resumed capital punishment in 1977, 80% were put to death for killing whites, while only 13% were executed for killing blacks.

The findings point to but one chilling conclusion: The criminal justice system places a higher value on the lives of whites than on the lives of blacks and other minorities. That means minorities who are victims of violent crimes are also victimized by a legal system that fails to provide them the "equal protection of the laws" they are guaranteed under the14th Amendment to the Constitution.

The report adds to the troubling evidence of racial discrimination against minority victims that has surfaced in other, state-level studies over the past year:

In Illinois, juries have been three times as likely to sentence a person to death if the victim is white rather than black. Then-Gov. George Ryan cited those findings in January, when he commuted 167 death sentences to life imprisonment.

In Maryland, the death penalty is four times as likely to be imposed when the victim is white rather than black. But a moratorium on executions imposed by the outgoing governor has been revoked by his successor.

Other studies in New Jersey, North Carolina, Pennsylvania, Texas and Virginia have shown similar results, as did a review a decade ago by the U.S. General Accounting Office, the investigative arm of Congress.

Other research suggests race-based differences in administering justice are not unique to the death penalty. A major study published by Stanford University in 1995 found that prosecutors tended to stereotype nonwhite crime victims as less-convincing witnesses, and cases involving nonwhite victims were more likely to be dismissed or result in plea-bargains to lesser penalties.

The Supreme Court banned the death penalty in 1972 after finding it was imposed arbitrarily. Four years later capital punishment was reinstated based on the claim that new laws would guide judges and juries to mete out death sentences evenhandedly.

The record since then shows the court was right the first time. When a victim's skin color is key in deciding who is put to death, the system not only violates constitutional protections but also is corrupt.

A better alternative to the death penalty is life imprisonment without parole. It protects society from those who commit heinous crimes without perpetuating a deadly system of unequal justice based on race.